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arXiv · 1901.09627

Twisted toroidal Lie algebras and Moody-Rao-Yokonuma presentation

Fulin Chen·Naihuan Jing·Fei Kong·Shaobin Tan
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Abstract

Let $\fg$ be an affine Kac-Moody algebra, and $\mu$ a diagram automorphism of $\fg$. In this paper, we give an explicit realization for the universal central extension $\wh\fg[\mu]$ of the twisted loop algebra of $\fg$ related to $\mu$, which provides a Moody-Rao-Yokonuma presentation for the algebra $\wh\fg[\mu]$ when $\mu$ is non-transitive, and the presentation is indeed related to the quantization of toroidal Lie algebras.

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Fulin Chen, Naihuan Jing, Fei Kong, Shaobin Tan. 2019-01-28. Twisted toroidal Lie algebras and Moody-Rao-Yokonuma presentation. https://doi.org/10.1007/s11425-019-1615-x

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